The author used different formulations of silver nanoparticles and bamboo cellulose crystals to heal up the wound on mouse skin surface.
In such an experiment, it is obligatory that different mouse should be used to treat with different formulations made. This is to ensure the impact of any formulation on the wound healing or combating with the disease.
However, the author has chosen the same mouse again and again to check the effect of different formulations. Like Yellow and blue color enclosed photographs indicate the same mouse used to treat with different formulations i.e. UC, DH-CNCs, BB-CNCs treatment for one and Bet and AgNPs for another mouse.
Similar is the case with other panels corresponding to the days after treatment i.e. 3 and 18 days. Purple, green, orange and red color enclosed photographs represents the same mouse again for different treatments.